| 1. |
- Abele, H., et al.
(author)
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Particle physics at the European Spallation Source
- 2023
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In: Physics reports. - : Elsevier. - 0370-1573 .- 1873-6270. ; 1023, s. 1-84
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Research review (peer-reviewed)abstract
- Presently under construction in Lund, Sweden, the European Spallation Source (ESS) will be the world’s brightest neutron source. As such, it has the potential for a particle physics program with a unique reach and which is complementary to that available at other facilities. This paper describes proposed particle physics activities for the ESS. These encompass the exploitation of both the neutrons and neutrinos produced at the ESS for high precision (sensitivity) measurements (searches).
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| 2. |
- Andersson, Erik, et al.
(author)
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Ambio fit for the 2020s
- 2022
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In: Ambio. - : Springer Nature. - 0044-7447 .- 1654-7209. ; 51:5, s. 1091-1093
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Journal article (peer-reviewed)
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| 3. |
- Baran, Jakub, 1980, et al.
(author)
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On the stability of single-walled carbon nanotubes and their binding strengths
- 2012
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In: Theoretical Chemistry Accounts. - : Springer Science and Business Media LLC. - 1432-881X .- 1432-2234. ; 131:9, s. 1-8
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Journal article (peer-reviewed)abstract
- We have studied the relative stability of hydrogen-terminated single-walled carbon nanotubes (SWNTs) segments, and open-ended SWNT fragments of varying diameter and chirality that are present at the interface of the catalytic metal particles during growth. We have found that hydrogen-terminated SWNTs differ by < 1 eV in stability among different chiralities, which presents a challenge for selective and property-controlled growth. In addition, both zigzag and armchair tubes can be the most stable chirality of hydrogen-terminated SWNTs, which is a fundamental obstacle for property-controlled growth utilizing thermodynamic stability. In contrast, the most armchair-like open-ended SWNTs segments are always the most stable ones, followed in sequence by chiral index up to the least stable zigzag segments. We explain the ordering by triple bond stabilization of the carbon dangling bonds at the open ends, which is a fragment stabilization effect that is only manifested when all bonds between two layers are broken. We show convincingly that the bond strength difference between zigzag and armchair tubes is not present when individual bonds are broken or formed. © Springer-Verlag 2012.
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| 4. |
- Harder, Robin, 1983, et al.
(author)
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Quantification of goods purchases and waste generation at the level of individual households
- 2014
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In: Journal of Industrial Ecology. - : Blackwell Publishing. - 1088-1980 .- 1530-9290. ; 18:2, s. 227-241
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Journal article (peer-reviewed)abstract
- Quantifying differences in resource use and waste generation between individual households and exploring the reasons for the variations observed implies the need for disaggregated data on household activities and related physical flows. The collection of disaggregated data for water use, gas use, electricity use, and mobility has been reported in the literature and is normally achieved through sensors and computational algorithms. This study focuses on collecting disaggregated data for goods consumption and related waste generation at the level of individual households. To this end, two data collection approaches were devised and evaluated: (1) triangulating shopping receipt analysis and waste component analysis and (2) tracking goods consumption and waste generation using a smartphone. A case study on two households demonstrated that it is possible to collect quantitative data on goods consumption and related waste generation on a per unit basis for individual households. The study suggested that the type of data collected can be relevant in a number of different research contexts: eco-feedback; user-centered research; living-lab research; and life cycle impacts of household consumption. The approaches presented in this study are most applicable in the context of user-centered or living-lab research. For the other contexts, alternative data sources (e.g., retailers and producers) may be better suited to data collection on larger samples, though at a lesser level of detail, compared with the two data collection approaches devised and evaluated in this study.
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| 5. |
- Holmberg, Jonas, 1976-, et al.
(author)
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Machining of additively manufactured alloy 718 in as-built and heat-treated condition: surface integrity and cutting tool wear
- 2024
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In: The International Journal of Advanced Manufacturing Technology. - : Springer Nature. - 0268-3768 .- 1433-3015. ; 130:3-4, s. 1823-1842
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Journal article (peer-reviewed)abstract
- Additive manufacturing (AM) using powder bed fusion is becoming a mature technology that offers great possibilities and design freedom for manufacturing of near net shape components. However, for many gas turbine and aerospace applications, machining is still required, which motivates further research on the machinability and work piece integrity of additive-manufactured superalloys. In this work, turning tests have been performed on components made with both Powder Bed Fusion for Laser Beam (PBF-LB) and Electron Beam (PBF-EB) in as-built and heat-treated conditions. The two AM processes and the respective heat-treatments have generated different microstructural features that have a great impact on both the tool wear and the work piece surface integrity. The results show that the PBF-EB components have relatively lower geometrical accuracy, a rough surface topography, a coarse microstructure with hard precipitates and low residual stresses after printing. Turning of the PBF-EB material results in high cutting tool wear, which induces moderate tensile surface stresses that are balanced by deep compressive stresses and a superficial deformed surface that is greater for the heat-treated material. In comparison, the PBF-LB components have a higher geometrical accuracy, a relatively smooth topography and a fine microstructure, but with high tensile stresses after printing. Machining of PBF-LB material resulted in higher tool wear for the heat-treated material, increase of 49%, and significantly higher tensile surface stresses followed by shallower compressive stresses below the surface compared to the PBF-EB materials, but with no superficially deformed surface. It is further observed an 87% higher tool wear for PBF-EB in as-built condition and 43% in the heat-treated condition compared to the PBF-LB material. These results show that the selection of cutting tools and cutting settings are critical, which requires the development of suitable machining parameters that are designed for the microstructure of the material.
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| 6. |
- Isaksson, Raine, et al.
(author)
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Supplementary Cementitious Materials in Building Blocks—Diagnosing Opportunities in Sub-Saharan Africa
- 2023
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In: Sustainability. - : MDPI. - 2071-1050. ; 15:7
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Journal article (peer-reviewed)abstract
- Sustainable building should at least be affordable and carbon neutral. Sub-Saharan Africa (SSA) is a region struggling with housing affordability. Residential buildings are often constructed using block-based materials. These are increasingly produced using ordinary Portland cement (PC), which has a high carbon footprint. Using alternative Supplementary Cementitious Materials (SCMs) for block production might reduce the footprint and price. The purpose is to assess the level of information for SCM use in blocks in SSA and to use this information for Diagnosing the improvement potential as part of an Opportunity Study. Results from the scoping review show that aggregated information on SCMs and the quantities available is limited. Diagnosing the theoretical improvement potential in using cassava peel ash, rice husk ash, corn cob ash, volcanic ash and calcined clays, indicates that SCMs could represent a yearly value of approximately USD 400 million, which could be transferred from buying cement to local production. The use of SCMs could save 1.7 million tonnes of CO2 per year and create some 50,000 jobs. About 5% of the PC used for block production could be substituted, indicating that, in addition to using SCMs, other solutions are needed to secure production of sustainable blocks.
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| 7. |
- Siva Subramaniam, Vanajah, 1971, et al.
(author)
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The support of Quality Management to sustainable development: a literature review
- 2016
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In: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526 .- 1879-1786. ; 138:2, s. 148-157
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Journal article (peer-reviewed)abstract
- Quality Management is considered to be suitable as support for the integration of sustainability considerations in areas such as product development. The purpose of this paper is to review research in which Quality Management methods, tools or practices have been used in conjunction with sustainable development initiatives. We have identified four themes that synthesize the research on Quality Management and its support to approaches for sustainable development: (I) supporting sustainability through integration of management systems, (II) Quality Management as support to the implementation of Environmental Management Systems and to the management of sustainability, (III) supporting integration of sustainability considerations in daily work, and (IV) supporting stakeholder management and customer focus. By far the most research has been conducted within the first two themes. This paper also contributes with proposals for future research, such as the need to move beyond existing standards and management systems to enable more radical improvements, and the need for empirical evidence of the effect of integrated management systems on environmental performance. We also highlight the point that Quality Management practices and tools must be developed and adapted in order to support sustainability considerations.
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| 8. |
- Tinetti, Giovanna, et al.
(author)
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The EChO science case
- 2015
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In: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 40:2-3, s. 329-391
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Journal article (peer-reviewed)abstract
- The discovery of almost two thousand exoplanets has revealed an unexpectedly diverse planet population. We see gas giants in few-day orbits, whole multi-planet systems within the orbit of Mercury, and new populations of planets with masses between that of the Earth and Neptune-all unknown in the Solar System. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in our Milky Way. The key science questions that urgently need addressing are therefore: What are exoplanets made of? Why are planets as they are? How do planetary systems work and what causes the exceptional diversity observed as compared to the Solar System? The EChO (Exoplanet Characterisation Observatory) space mission was conceived to take up the challenge to explain this diversity in terms of formation, evolution, internal structure and planet and atmospheric composition. This requires in-depth spectroscopic knowledge of the atmospheres of a large and well-defined planet sample for which precise physical, chemical and dynamical information can be obtained. In order to fulfil this ambitious scientific program, EChO was designed as a dedicated survey mission for transit and eclipse spectroscopy capable of observing a large, diverse and well-defined planet sample within its 4-year mission lifetime. The transit and eclipse spectroscopy method, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allows us to measure atmospheric signals from the planet at levels of at least 10(-4) relative to the star. This can only be achieved in conjunction with a carefully designed stable payload and satellite platform. It is also necessary to provide broad instantaneous wavelength coverage to detect as many molecular species as possible, to probe the thermal structure of the planetary atmospheres and to correct for the contaminating effects of the stellar photosphere. This requires wavelength coverage of at least 0.55 to 11 mu m with a goal of covering from 0.4 to 16 mu m. Only modest spectral resolving power is needed, with R similar to 300 for wavelengths less than 5 mu m and R similar to 30 for wavelengths greater than this. The transit spectroscopy technique means that no spatial resolution is required. A telescope collecting area of about 1 m(2) is sufficiently large to achieve the necessary spectro-photometric precision: for the Phase A study a 1.13 m(2) telescope, diffraction limited at 3 mu m has been adopted. Placing the satellite at L2 provides a cold and stable thermal environment as well as a large field of regard to allow efficient time-critical observation of targets randomly distributed over the sky. EChO has been conceived to achieve a single goal: exoplanet spectroscopy. The spectral coverage and signal-to-noise to be achieved by EChO, thanks to its high stability and dedicated design, would be a game changer by allowing atmospheric composition to be measured with unparalleled exactness: at least a factor 10 more precise and a factor 10 to 1000 more accurate than current observations. This would enable the detection of molecular abundances three orders of magnitude lower than currently possible and a fourfold increase from the handful of molecules detected to date. Combining these data with estimates of planetary bulk compositions from accurate measurements of their radii and masses would allow degeneracies associated with planetary interior modelling to be broken, giving unique insight into the interior structure and elemental abundances of these alien worlds. EChO would allow scientists to study exoplanets both as a population and as individuals. The mission can target super-Earths, Neptune-like, and Jupiter-like planets, in the very hot to temperate zones (planet temperatures of 300-3000 K) of F to M-type host stars. The EChO core science would be delivered by a three-tier survey. The EChO Chemical Census: This is a broad survey of a few-hundred exoplanets, which allows us to explore the spectroscopic and chemical diversity of the exoplanet population as a whole. The EChO Origin: This is a deep survey of a subsample of tens of exoplanets for which significantly higher signal to noise and spectral resolution spectra can be obtained to explain the origin of the exoplanet diversity (such as formation mechanisms, chemical processes, atmospheric escape). The EChO Rosetta Stones: This is an ultra-high accuracy survey targeting a subsample of select exoplanets. These will be the bright "benchmark" cases for which a large number of measurements would be taken to explore temporal variations, and to obtain two and three dimensional spatial information on the atmospheric conditions through eclipse-mapping techniques. If EChO were launched today, the exoplanets currently observed are sufficient to provide a large and diverse sample. The Chemical Census survey would consist of > 160 exoplanets with a range of planetary sizes, temperatures, orbital parameters and stellar host properties. Additionally, over the next 10 years, several new ground- and space-based transit photometric surveys and missions will come on-line (e.g. NGTS, CHEOPS, TESS, PLATO), which will specifically focus on finding bright, nearby systems. The current rapid rate of discovery would allow the target list to be further optimised in the years prior to EChO's launch and enable the atmospheric characterisation of hundreds of planets.
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